The White House asked New York Gov. David Paterson to step aside at least in part because the administration was asked to intervene by members of Congress and state legislators who raised serious alarms about a potential Paterson drag on the ticket in 2010.

The issue is no small matter in a state with an appointed senator running statewide for the first time in 2010 and more than a half-dozen vulnerable House Democrats — including five freshmen.

According to interviews with New York Democrats, the request for intervention came from both Albany and Washington, where Paterson’s precarious political standing unnerved many officeholders who are worried about the prospect of running in a midterm election with a deeply unpopular incumbent at the top of the ballot.

“Clearly, the situation in New York is unusual and requires leadership at a greater level than anyone in New York can provide,” said Rep. Dan Maffei, a first-term Democrat who occupies a seat in upstate New York. “I, for one, welcome the president’s involvement.”

The request for Paterson to step aside and not seek a full term, multiple sources said, has been in the works for weeks.

“It’s hard to argue that he can excite a lot of voters at this point,” said one New York House member.

Two senior Democratic officials, speaking on the condition of anonymity, said members of the House delegation had sent a strong message to White House chief of staff Rahm Emanuel in closed-door meetings that it was time for Paterson to move on.

These Democrats said their chief concern was that with Paterson on the ballot, the party would see a sharp drop-off in turnout across the state.

“I think that the role that Paterson plays in all of this is that he can affect turnout,” said Lee Miringoff of the Marist Institute for Public Opinion. “When you have the top of the ticket not running well, that affects everyone.”

Freshman Democratic Rep. Mike McMahon, who won a Republican-leaning Staten Island-based seat in 2008, agreed with that assessment.

“I think, as a quintessential down-ballot candidate, as a freshman seeking reelection, I am, of course, concerned about the top of the ticket because the top of the ticket determines turnout,” he said. “I am pleased that the White House is concerned about the issue.”

“It’s important that we as a Democratic team have the best team up and down the ticket, and that’s what we’re doing,” said McMahon.

Tuesday brought more bad news for Paterson, with the release of a Siena College poll showing his favorability rating at just 29 percent and only 14 percent in favor of reelecting him.

But the rationale for intervening in New York is different. The fear among some legislators is that Paterson stands to affect the party up and down the line in a state with an unusually high number of recently elected members who have not yet locked down their seats. The list begins with Kirsten Gillibrand, the Democratic senator he appointed in January to fill Hillary Clinton’s vacant seat.

Gillibrand’s own poll ratings have been weak — only 26 percent of voters participating in Marist’s September survey approved of her job performance — and there is concern in some Democratic circles that former Republican Gov. George Pataki could challenge her in 2010.

“The White House would consider it a huge disappointment losing a Senate seat in New York,” said Miringoff. “It’s not what you want as a party.”

Gillibrand declined to discuss Paterson when approached by POLITICO off the Senate floor Tuesday evening. Her spokesman did not respond to a request for comment.

Aside from Gillibrand, there are seven House Democrats who face potentially competitive reelection bids, including Rep. Scott Murphy, who won Gillibrand’s old House seat in a special election earlier this year by roughly 700 votes.

“In New York, in as challenging a year as 2010 inevitably will be because of historical trends, you want to make sure that you are strong ... and that you don’t have to focus on [it],” said Maffei.

“If the leader of the party, the president, has to worry about New York House seats, New York Senate seats — not to mention the governor’s seat itself — then it will be a lot of resources ... that can’t be used in other places where we will face a challenge in 2010,” he said.

And there is also significant concern within the party that, should Democrats lose a host of state legislative seats next fall, it would significantly weaken their position in the upcoming fight over redistricting.

“If you have a weak top of the ticket, not only would we lose some of our House members, we would lose some of the state Senate seats, and if we lose the Senate, we lose control of redistricting,” said the House member.

Publicly and privately, Paterson has resisted the calls from the White House to stand down. On Tuesday, he told reporters defiantly, “You don’t give up.”

Rep. Steve Israel, a Long Island Democrat, said he came away from a five-minute phone conversation with Paterson with the feeling that Paterson was “steadfast” in his determination not to back down in the face of pressure.

“He didn’t give me any indication that he is packing his bags,” said Israel.